Spring member



Oct. 29, 1929. G. H. BEAUMONT ET AL SPRING MEMBER Filed Oct. 18, 1926 mmB INVENTORS ATTORNEY Fatented Oct. 29, 1929 STATES PATENT OFFICE GEORGEH. BEAUMONT, AND JOHN C. .MONTEI'IH, OF CLEVELAND, OHIO, ASSIGNORS TOSTERLING SPRING COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF DELA- WARE' SPRING MEMBER Application filed October 18, 1926.

This invention relates to springs for absorbing shocks, and moreparticularly to an attachment for controlling the action of vehiclesprings.

Vehicle springs of the semi-elliptic type have heretofore generally beendesigned to have practically the same properties in com pressicn as inrecoil. hen such a spring is compressed in response to a road shock, theforce is transmitted to the vehicle chassis in a manner determined bythe characteristics and dimensions of the particular spring. As ageneral proposition it may be stated that a spring which respondsreadily to road shocks will readily transmit these shocks to the vehiclebody. Cm the other hand, a spring which will not transmit shocks readilyto the vehicle body will be sluggish in responding to road shocks. Thesesprings have an added disadvantage, particularly when employed inconnection with vehicles equipped with balloon tires, of going intovibration in synclironisni with the vibrations transmitted by the tiresthereby causing the chassis to oscillate in a disagreeable and possiblya dangerous manner until the synchronization is broken up by changingthe speed of the vehicle, or in some other manner.

By means of the controller for vehicle springs constructed in accordancewith this invention the upward movement of the spring in recoil isretarded so that the shock transmitted to the vehicle chassisisc'onsiderably less than that received by the wheels. By retarding themovement in one direction the tendency of the spring to oscillate insynchronism with road shocks is reduced. The oscillations of the springare broken up by causing it to have dilferent natural periods ofvibration in compression and expansion so that the tendency to oscillateat either of these frequencies is opposed by the spring beingnon-synchronous to that frequency in one-half its cycle of movement.

The present invention comprises a resilient member which may be rigidlyattached to a chassis spring and placed in reverse compression withrespect thereto so that a false load is applied to'the spring by thecontroller for assisting the spring in downward movement Serial No.142,184.

but retarding it in recoil, whereby the full force of the impact isprevented from being exerted upon the chassis.

Although the novel features which are believed to be characteristic ofthis invention will be pointed out with particularity in the claimsappended hereto, the invention itself as to its objects and advantages,the manner of its operation and the mode of its organization, may bebetter understood by referring to the following description taken inconnection with the accompanying drawings forming a part thereof, inwhich:

Fig. 1 is an elevation of the controller applied to a semi-ellipticspring member;

F 1g. 2 is an elevation of the spring assembly connected to a vehicleframe of conventional type;

Fig. 8 is a sect-ion taken on the line 3-3 of Fig. 1

a Fig. at is a section taken on the line H of rig. 1; and

Fig. 5 shows a modified means for attaching the controller to thespring.

In the following description and in the claims parts will be identifiedby specific names for convenience, but they are intended to be asgeneric in their application to similar parts as the art will permit.

Referring to the drawings more in detail, the spring attachmentconstructed in accordance with this invention is illustrated as appliedto a conventional type of semi-elliptic spring member 10 including anupper leaf 11 which is extended at its two ends to form knuckles 12 and13 to facilitate connection to a vehicle chassis. A series of leaves ofprogressively decreasing length are connected to leaf 11 in the usualmanner by means of bolt 16 which passes through the center of the entireassembly. The spring may be connected to a supporting member such as anaxle in any well known manner. In the construction shown for purposes ofillustration a U-bolt 17 is passed around axle 18 on either side ofspring 10 and clamped to the spring by plate 19. Clips 14: and 15surround certain of the leaves near their free ends and preventseparation thereof during recoil causing the various leaves to assist inpreventing an excessive reverse movement of the spring.

The auxiliary controlling attachment comprises resilient leaves 20 and21 which are attached at one end near the center portion of the mainspring, the center portion being considered for convenience ofdescription as the stationary portion of the main spring. The other endof leaves 20 and 21 are secured at or near the free end of the chassisspring in such manner that the two springs are held in reversecompression. As shown in the drawings, leaves 20 and 21 are attached tothe main spring by means of clevis 24; and cross bar 22 ata point nearthat to which the vehicle axle is attached. Clevis 2e surrounds the mainspring and extends through holes in cross bar 22, the latter beingcaused to firmly clamp leaves 20 and 21 to the main spring leaves bymeans of nuts 25 which are threaded upon the ends of clevis 24 passingthrough cross bar 22.

Leaves 20 and 21 are rigidly attached to cross bar 22 by means of rivets23 which are passed through the various members. The

free ends of leaves 20 and 21 are clamped to the free end of the mainspring member 10 by means of clevis 30 which surrounds the main springmember, said clevis cooperating with cross bar 31 upon which leaves 20and 21 rest. Clevis 30 passes through holes in cross bar 3 1 and issecured thereto by means of nuts 32 which are placed upon thethreadedends of the clevis.

Leaf 21 is secured to cross bar 31 by means of rivets 33 which passthrough the two members. Leaf 20, and any additional leaves which it maybe found necessary to employ, rest upon and are supported by leaf 21,but in order to provide for slippage during flexure and minimizefriction, are not rigidly secured thereto at their free ends.

In attaching the controller to the main spring, clevis 24 is firstsecurely clamped in position about the center portion of the spring asvshown in Fig. 1. Clevis 30 is then passed around the free end of themain spring andtension applied thereto by tightening the nuts 32,thereby flexing the leaves of the controller and causing them to apply aforce to the leaves of the main spring. The two springs are thus held inreverse compression,

the extent of which may be controlled and regulated by adjusting thetension of clevis 30.

The controller applied as above described introduces a false load uponthe main spring throughout the normal length of movement thereof andassists it in compression. The movement of the main spring in recoil ishow ever retarded by the downward pull exerted by the controller and therate of movement in recoil is decreased to such an extent that any heavyshock received by the wheels is not freely transmitted through thespring to the chassis as a sharp shock but is largely absorbed by thespring itself.

In the arrangement above described the compression resistance of theentire spring assembly is equal to that of the main spring plus that ofthe controller itself. The spring is therefore stiffened by the additionof the controller and the compression resistance increased. Thecontrollerincreases the load which the main spring can carry, but byassisting the main spring in compression and retardingit in a recoilimparts properties thereto which would not be obtained by the use of asingle spring of compression resistance equal to the sum of that of themain spring and controller.

Various other features than the compression resistance must beconsidered in analyzing the riding quality of springs. A short springfor example will act more quickly than a long spring having the samecompression resistance, and will transmit a sharper shock to the vehiclechassis. The addition of the controller above described has an effectsimilar to that of altering the length of the spring. By assisting thedownward movement of the main spring the addition of the controller isequivalent to shortening the chassis spring and by retarding the upwardmovement in recoil the controller introduces properties similar tolengthening the main sprin The ultimateresult of the above two featuresis to allow a road shock transmitted through the wheels to the spring toquickly compress the latter and then to cause the spring to have aslower action in recoil, minimizing the shock transmitted to thechassis.

The spring assembly having different characteristics in compression andrecoil will not fall into synchronism with road shocks as the springwill have no pronounced natural period of vibration. The addition of thecontroller constructed in accordance with this invention produces theequivalent of a short spring in compression and a long spring in recoil.Since the above springs have different natural periods of vibration thespring as a whole will not oscillate in synchronism to shocks of eitherfrequency. The controller therefore effectively clamps oscillations atany frequency encountered in driving. This feature is particularlyimportant in vehicles equipped with balloon tires which at certainspeeds transmit road shocks of increasing amplitude to the vehiclechassis causing disagreeable vibration of the chassis until thesynchronism is broken up. Such types of vehicles when equipped with theabove described controller have been found to possess no disagreeablenatural period of vibration and are not forced into oscillation by roadshocks.

The adjustment of the force applied by the controller to the main springis extremely critical in certain cases as a very small change in therelative compresson of the two springs causes a marked difference in theriding quality of the chassis. The controller should be carefullydesigned to have the proper compression resistance to cooperate with theparticular spring and chassis to which it is tobe attached.

It has been found that by providing leaves of certain standard widthscorresponding to that of the chassis springs and by providing a range ofadjustment of the tension of the clevis surrounding the free ends of thespring, a few standard sizes may be employed, and, when installed, maybe properly adjusted to cooperate with the majority of the springs nowin use on pleasure automobile chassis.

Should the amount of flexure of the chassis spring be sufficiently greatto cause the controller leaves to pass through their free or inertpoint, the controller attached as disclosed in Fig. 1 would cease toexert a force upon the main spring. Should such be the case thecontroller may be attached as shown in Fig. 5 by the addition of crossbars a0 and 41 which are held against the controller and the main springrespectively by nuts 42 and 43.

In adjusting the controller attached in this manner, care must be takennot to rigidly clamp leaves 20 and 21 between cross bars 31 and 40 butto leave the adjustment sufficiently loose so that the movement of theleaves may take place as the spring is flexed. Cross bar 41 should beloosely engaged by the main spring member for the same reason. By theconstruction shown in Fig. 5, after the controller has reached its freeor inert point due to compression of the main spring, upon continueddownward movement, leaves 20 and 21 will be moved in the same directionas the main spring, and will oppose further movement.

The system disclosed in Fig. 5 need be employed only in case the extentof movement of the main spring is such that the controller moves pastits free point. The particular means for adjusting the controller to themain spring is shown by way of illustration only and any other suitablemeans for connecting the leaves of the two springs together and applyingreverse compression thereto may be employed if desired.

The above conception of the theory of operation of the controller hasbeen presented to more clearly set forth the invention, but is notintended as a limitation thereon.

l/Vhile we have shown and described and have pointed out in the annexedclaims certain novel features of the invention, it will be understoodthat various omissions, substitutions and changes in the forms anddetails of the device illustrated and in its operation may be made bythose skilled in the art without departing from the spirit of theinvention.

What is claimed is:

1. In combination with a vehicle chassis, a semi-elliptic spring memberattached thereto, said member being connected to a stationary member atits mid-point and to said chassis at its end points, an auxiliary leafspring, a cross member riveted to one end of said leaf spring, a clevissurrounding said main spring substantially at its center position andpassing through said cross member, means for maintaining said clevisunder tension whereby said spring member and auxiliary spring arerigidly connected together, a second crossbar at the other end of saidauxiliary spring rigidly connected to the lowermost auxiliary leafmember, a clevis surrounding said main spring at its free end andpassing through said second crossbar, and a pair of threaded members forapplying tension to the said last mentioned clevis whereby the auxiliaryspring may be maintained in reverse compression with respect to thespring member.

2. An auxiliary spring member comprising a plurality of spring leaves, across memher at each end thereof, one of said cross members beingrigidly connected to each of the said spring leaves, the other of thesaid cross members being rigidly connected to the adjacent spring leaf,a main semi-elliptic spring, a clevis passing through one of said crossmembers for rigidly attaching said auxiliary spring to said main spring,a clevis passing through the other of said cross members and adapted toco-operate with the main spring whereby each of said springs is heldunder compression and within normal range of movement of the main springwhich is assisted in movement in one direction by the auxiliary springand impeded in movement in the other direction thereby.

In testimony whereof we have hereunto set our hands.

GEORGE H. BEAUMONT. JOHN C. MONTIETH.

